Implement for truing crank pins and effecting like operations



Sept. 25, 1923. 1,468,952

- F. BADCOCK IMPLEMENT FOR TRUING CRANK PINS AND EFFECTING LIKEOPERATIONS Filed Feb. 16. 1922 Patented Sept."25, 1923.

* cams 'A FRED Ban'cocK, 0}? LONDONQENGIIJAND, Assreivoe oE-oitE-rrALrro H-ILL KANE, or noimon, ENGLAND.

Par-s mPIiEmT" #0 1 crmfik" rims ANii-EFFEGTIN iirKE OPERATION-S4: f

it known that I, ERED*BADCOCK, a suhjcct of the*King of, En land;residing ai'n" 'rmden, Eii'glarfid, have invented certai newand usefulImprovements in- Imp1e'-' Inentsf for Truing Crank Pins and Effectinglike Operations; of which the following is a specification,

object to provide" a hand operatedimplement which can b'e' 'read ilyplacedround" the crank-pin and rotated about-the same to trueitwithout'having to' mount the; crank shaft' in any? apparatus otherthansome means to hold it.

, An implementaccording to the present invention comprises incombination a'- dirigidly secured together, tw'ir'o' or more intvardlykproject ing' guide-tool's; and a single inwardly projecting cuttin tothe said guide-tools.

Preferably more} than two guide-tools are employed and the cuttiiig too1"'is opposite 'one' of said guide-tools Which 1ies betWeen-' twootherss' Thus 1 in the example-t "be de scribed hereinafter, there are;three-guide tools spaced approximately 90 fromeach other, and thecutting-tool is opposite the central one of the three.

Means are' "provided;- according to another feature of the inventior'rto-a'djust' the tools toward's 'and away from the centre of the I planeof the slot 22: V

The opposed faces of-each'slotiare paral- 90 The frame is formed on'itsouter edge with bosses 26; one opposite each of the} slots in the Webs,-and a hole 28 is implement independently of each-- other;

For example thetools are mounted to slide inapproX-imately' radialguides and arcadjustable thereinby means of adjusting-Z screws.

Other features ofthe invention consist in aspecial form= of ui'd'eSrOrthe tco'Li'n eluding aresilient guide member, an adva'n tageousarrangement in the fr'ame ofithe cutting tool and a particular shapethereof, and a particular relation-between the'operating' handle andthecutting-tool; which ensure exact parallelism of the tools and a smo0th cutting action Without? chattering; I

These featureswill'lbeim l i fined in peii'ded claiinsi- Ah implementaccordii'g tethieinventiqn g t'ool opposed;

particularly" de nie'rit with a part ins'ectionf Figure l is'asideelevation of the imple F igur'e'2is a perspe'ctir'e View of the'ting;too1, and

is illustrated in the accoinpanyiiig drawings; 1

RIcHA-Rn WILLIS:

Figure" 3 is a section on lthe line'3 -3 in l Figure 2, looking in thedirection of the arrow; 7

The frame of the implement comprisesif tWocastings 2, 4, of generallysemi circular shape having their meeting" faces 6 ma-.

chined to' an, accurate fit; Studs Share screwed into bosses lOion thepart? 2 ofthe frame and extend through holes- (which i they'fitaccurately) hr corre'sponding'bo sses 12 on the part4; Nuts 14are'secured on the protruding ends of the. studs 8, so that the twoparts'of the frame may-he readily separated and re-assembledLrigid-lyinexact register. I

Eachfpart of the frame hasan inward centrally disposed Web 16, 18recessed as at 18 'o'1i'one side for lightness the faces of this webbeing. machined flat and parallel;

Two slots are cut in eachwe'b, and thecen trail-planes of the slots201in the web, 16 are radial to the central axis of the itrame,:in'clined' to each other at and tothe n1eetfslightly displaced from, andparallel' to, a

18 also has its radial plane" inclined at 90 to the central i lel; andallthe slots extend from side to side of the Webs,

rest and is threaded to receive an adjusting screw to be describedherelnafter.

The radialslots 20, 22 1 eceive guide-tools 82', and theslot 9Areceivescutting-tool34:. Thethi'ckn'ess ofthetjools i'ssuch as'tofbe aand breaking through-intoit: IA'part 30of each "hole is ofsmallerdiameterthan the worki g fit" in the slots, their Width isslightly greater thansthe thickness of the 5 I webs, and their sides areslightly rounded,

the slightly projecting sides of the tools. Being thus held tightlyagainst the firni abutment provided by the plates 36, the

tools are always held. with their active faces laterally.

perfectly parallel. By removing one of the guide-plates 38, a tool maybe removed A groove 42 is cut in one face of eachtool near its outerend, which receives the shouldered end 44 of the adjusting screw 46, asshown in the sectional part of Figure 1. Each screw 46 is provided witha squared outer end to be engaged by a key whereby the tools may beadjusted radially in the slots as will be readily understood.

The end faces of the widened inner extremities 48 of the guide-tools 32are plane surfaces perpendicular to the faces of the tools and parallelto the central axis of the implement. These faces are hardened tominimize wear.

The widened inner extremity 50 of the cutting-tool 34 is shaped to forma cutting edge which lies on or near the central plane of the toolitself and is parallel tothe central axis. of the implement. I Theextreme end face 52 of the tool, which forms the clearance face of theedge, is made perpendicular to the faces of the shank of the'tool, thenecessary clearance being provided by the displaced location of the;tool, as will be readily understood. It will of course be appreciatedthat the cutting edge faces he radial plane parallel to the centralplane of the tool, as shown in Figure 1.

An important advantage of the shape and location of the tool 34L is thatif the tool bends slightly when taking a cut, the cutting edge recedesfrom the work by a very slight amount, thus preventing chattering andensuring a smooth cut.

Further, the angle of the face 52 enables the tool to be sharpened inthe following manner A square-edged oil-stone isplaced ona flat surface,together with the tool, one of the faces of the shank of which rests onthe flat surface. The face 52 is then brought against the edge of theoil-stone and rubbed along it with the oil-stone and tool kept firmly incontact with the flat surface. This ensuresthat the face 52 alwaysremains perpendicular to the faces of the shank. To test whether thecutting edgeis parallel to the central axis of the implement, aparallelsided block is inserted between the cuttingtool and the oppositeguide-tool, and the two tools are brought against the parallel sides ofthe block, when it "can at once-be seen whether the cutting-edge is incontact with the block along its whole length.

A removable handle 54 may be screwed into a socket 56 in the part 2 ofthe frame, the handle being about 60 in rear of the cutting-tool.Thislocati'on of the handle has been found advantageous in obtaining asmooth out and preventingchattering.

To use the implement intruing a crankpin, the two parts 2, ,4:- of theframe are separated and re-assembled round the pin. Thetools are then.advanced inwards by means of the adjustingscrews until they touch thesurface of the pin and the iniplei'nent is ro'- V tat ed by means of thehandle 54 and ad vanced along the pin until a cut has been takenalong'the whole of its length. "The tools are then again advanced andthe process repeated until the pin is truly circular.

To assist in adjusting the tools, a seriesof concentric circles. (notshown in the drawing) is scribed on the unrecessed face of the webs 16,1%, and care is'taken in adjusting the tools that heir outerendsare-approximately the same distance from. one of the I circles. This ensures that all the tools bear on the crank-pinor the like in themenus intended. I V

It is found that with this implement great accuracy can be obtained andthe work is quickly carriedout'leaving the pin-with a smooth finish. V 7

Obviously, the implement is not restricted to its main use, namely, thatof truing the pins of crankshafts, but can be used to true any, part ofa shaft or other member by' hand, for example, black shafting could betrued u'pby this implement at points Where bearings are to be provided.

A further advantage of the'independent adjustment of the guide-tools andcutting tool is that they enable a proper position to be found for thecutting-tool for all sizes of, pin which the implement is intended toaccommodate. 7

Although it is preferred to use three guide-tools and one cuttingtool,particularly 1. In an implement for truing crank-pins V and efiectinglike operations, the combination w1th an annular frame having aplurality of spaced parallel-sidedslots eXtending approximately radiallyfrom the inner" inwardly-projecting tools having parallelsided shankseach mounted to slide in one of said slots, a plurality of guide-platesse cured to the faces of the frame to close the open sides of said slotsand adapted to bear against the exposed sides of the shanks of the toolsto guide them, and means for independently adjusting each ,toollengthwise of the slot in which it is mounted.

2. In an implement for truing crank-pins and effecting like operations,the combination with an annular frame having a plurality of spacedparallel-sided slots extending approximately radially from the inneredge of said annular frame and open on both faces of said frame, of aplurality of inwardly-projecting tools having parallelsided shanks eachmounted to slide in one of said slots, the width of said shanks beingslightly greater than the thickness of said frame at the, slotted partthereof, a plurality of guide-plates rigidly secured to the frame toclose the open sides of said slots on one side of the frame, and aplurality of resilient guide-plates secured to the other side of theframe and adapted to bear against the exposed and slightly projectingsides of the shanks of the tools on said other side.

3. In an implement for truing crank-pins and effecting like operations,the combination with a divided annular frame having a plurality ofradial guide-ways and a nonradial guide-way opposed to. one of saidradial guide-ways, of means for rigidly securing the parts of' saidframe together, a plurality of inwardly-projecting guidetools eachmounted in one of said radial guide-ways, a single inwardly-projectingcutting-tool mounted ,in the non-radial guide-way, which latter isparallel to a plane radial to the central axis of rotation of theimplement and slightly in rear thereof in relationto the'direction ofrotation of the implement, the cutting edge of the cut ting tool lyingin rear of that radial plane of the frame that extends through thelongitudinal axis of the opposed guide-tool,

and means for independently adjusting each the frame that extendsthrough the longitudinal axis of the opposed guide-tool, and a radialhandle secured to said frame in rear of said cutting-tool in relation tothe direction of rotation of the implement.

securing the parts thereof together, a pIurality of inwardly-projectingguide-tools mounted in said frame, and a single inwardly-projectingcutting-tool opposed to one of said guide-tools and having-a. shankmounted in said frame parallel to but slightly in rear of that radialplane of the implement which extends through the longitudinal axis ofthat guide-tool oppositethe cutting- 7 face ofits cutting edgeperpendicular to the i length of the shank. V

6. An implement for truing crank-pins tool, said'cutting-tool havingthe'clearance;

and effecting like operations, which 'comprises in combination a dividedannular frame having four' parallel-sided slots extending from the inneredge of said annular frame, open on both faces of said frame and spacedat, angular. intervals of approximately threeof said slots being radialand the fourth non-radial, means for rigidly securing the parts of theframe together, four inwardly-projecting adjustable tools comprisingthree guide tools and a cuttingj tool, each having parallel-sided shanksmounted to slide. in one of said slots, the

width of said'shanks being slightly greater than the thickness of saidframe at the slotted part thereof, four guide-plates rig- T idly securedto the frame to close the open four resilient guide-plates secured tothe other side of'the frame and adapted to'bear against the exposed andslightly projecting sides of the shanks of the tools onsaid other side,means for independently adjusting each tool lengthwise in its slot, thecuttingtool being mounted in the non-radial slot side of said slots onone side of said frame, v.

with its cutting edge lying'to the rear of that. radial plane of theframe which extends through the longitudinal axis of the opposedguide-tool, and a radial handle se cured to said frame in rear of saidcutting-V tool in relation to the direction of rotation ofthe implement.In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses. V V

' V FRED BADCOCK. Witnesses:

ARTHUR O. DUCOMBE, REGINALD J. RIDGEWELL,

